Workaround metro not compiling static properties correctly.

[miracle2k]

Fixes the issue we encountered #406 (comment)

To review, the problem is as follows:

The correct syntax is:

static propTypes = {
    ...GenericTouchable.internalPropTypes
}

Metro/Babel compiles this to:

// Define GenericTouchable
GenericTouchable.propTypes = (0, _objectSpread2.default)({}, GenericTouchable.internalPropTypes, GenericTouchable.publicPropTypes);

But when metro then runs the HMR transform, this becomes:

// Create _class
_class.propTypes = (0, _objectSpread2.default)({}, GenericTouchable.internalPropTypes, GenericTouchable.publicPropTypes),

It rewrites the class name to _class during initialization, but misses the references in the spread, which then causes a undefined-access exception.

See this Gist for full outputs: https://gist.github.com/miracle2k/3bc7f1c50080397dbf0d92cfb3101677#file-generictouchable-babel-with-metro-preset-js

Part of the problem seems to be that metro uses a very old version of react-hot-loader.

The code as it is currently in the library, using ...this.publicPropTypes has two problems: First, it does not compile at all with babel, when this library becomes imported as part of using react-native-web.

Second, while it does compile using metro, the generated code instead will be:

// Create _class
_class.propTypes = (0, _objectSpread2.default)({}, this.internalPropTypes, this.publicPropTypes),

With this probably referring to the window or global scope, thus not causing a crash, but not actually setting the proptypes correctly.

[osdnk]

Thanks, I had an intuition that's incorrect, but I have encountered the problem you've mentioned, so I found solution I committed workable and then leave it as temporary fix, which I forgot about. Sorry guys.

[osdnk]

💯